OK-TVI

Airframe no.: 0.06

Energia designation: 6M

Alternative designations: OK-TVI

OK-TVI — Orbitalniy Korabl — Termo-Vakuumnyye Ispytaniya (Orbital Ship — Thermal-Vacuum Testing)

Almost complete segments of the airframe were used for thermal vacuum testing at NIIKhimmash in Peresvet, Moscow Oblast. The tests were performed to verify the characteristics of the orbiter across the full range of thermal conditions and heat flows expected in flight.

OK-TVI was divided into sections that would fit in the available thermal vacuum chambers: the forward fuselage and cabin, the mid and aft fuselage with payload bay doors, and the vertical stabilizer, which was the first to arrive at NIIKhimmash and was tested in the TVI-2 chamber from July 7 to July 25 1985.

Press enter or click to view image in full size Press enter or click to view image in full size The mid and aft fuselage section was transported by barge from the Molniya factory in Tushino along the Moscow canal to Dmitrov, where a special pier was built to unload the orbiter onto tractors. An additional bridge was built across the Velu River at Palchino; transportation was only carried out at night. OK-TVI’s fuselage finally arrived at NIIKhimmash on 9 October 1987.

There, the remaining thermal protection system tiles were installed, along with sensors and test equipment. The orbiter was transported to the test hall, where it underwent a comprehensive systems check. The fuselage was then lifted by two overhead cranes, rotated to a vertical orientation and lowered into the TVI-2 chamber. On 23 October 1990, the only planned run of the test program began. During the run, however, the thermal control system accidentally depressurized itself and a second run had to be conducted. By 10 December 1990 the fuselage testing in TVI-2 had concluded.

Press enter or click to view image in full size Press enter or click to view image in full size The main objectives of the TVI tests were determining the performance of temperature control systems in various operating modes (including emergency), determining the heat gradient and local temperature in parts of the airframe which experience the most heating, and refinement of calculation methods. The forward fuselage and cabin, which was equipped with “thermal equivalents” of onboard systems were used to test the cabin thermal control system (SOTR); the thermal equivalents were “turned on as required during flight simulation”. [10]

After work on the program stopped, OK-TVI remained at NIIKhimmash, gathering dust. Despite efforts by NIIKhimmash to convert the hardware into a museum exhibit, it was still owned by NPO Molniya, which decided to scrap OK-TVI in 2006. The only remaining part is the nose RCS cluster, which is exhibited at the test facility’s outdoor museum. [3]

Press enter or click to view image in full size Press enter or click to view image in full size OK-TVI at NIIKhimmash, October 3, 2002. Images: S.I. Pilipenko, V. Lukashevich via buran.ru/htm/006.htm